This invention relates to light and heat reflecting glazing units. These architectural glazing units are particularly suited for installation in the spandrel areas of curtainwall construction.
A spandrel area, as the term is used herein, refers to the opaque area, as contrasted to the vision area of a curtainwall, which is formed by the use of spandrel panels which are either intrinsically opaque or are rendered opaque by various backing or coating materials. Spandrel panels are designed to thermally isolate and conceal certain portions of the exterior structure of a building, as well as conceal interiorly located building fixtures. Thus, spandrel panels or spandrels are frequently employed to conceal floor slabs, the vertical span between floors and ceilings or between successive viewing closures, heating and air conditioning convectors and the like. Spandrel panels are principally employed to conceal those portions of a building that would not be aesthetically pleasing if capable of being viewed from the exterior of a building. However, spandrel panels also find use in building zones where it is desired to maintain a degree of privacy, such as at the ground level of a building.
In the past, various attempts have been directed toward producing spandrel panels that closely match or pleasingly contrast in color and reflectivity with adjacent, transparent glass panels in the viewing or vision areas of a building.
With the development of highly reflective transparent metal and metal oxide coatings, it has been an objective to develop spandrel panels which would match or harmonize with the coated glass vision panels to be glazed adjacent to spandrel panels. Because the back lighting conditions differ greatly from occupied spaces behind vision panels and service spaces or structural spaces behind spandrel panels, it has been difficult in the past to find spandrel panel combinations which could provide this matching or harmonizing appearance.